Hurrah: turn the thermostat up and am rewarded with the clunks, groans and gurgles that signify the heating is "working".
Bah: the top of the radiator in the Great Hall is stone cold.
Hurrah: application of key to bleed valve produces prolonged hissing, watery spurts and, ultimately, a radiator hot to the very top. Doubly Hurrah-worthy as bitter experience has shewn most radiator bleed valves to be made of cheese, requiring the services of a large adjustable spanner to do the Necessary.
Bah: this morning radiators are stone cold, boiler cryptically mutters "f.22". Intarwebs suggest that this means Larrington Towers will shortly catch fire, unless I've misunderstood.
Hurrah: application of screwdriver to relevant part of boiler puts pressure gauge back into the green; reboot of boiler produces clunks, groans, gurgles etc.
Bah: my feet are still bloody freezing.